(a) Field of the Invention
The present invention relates to a perpendicularly magnetized thin film structure and a method of manufacturing the same. In more detail, the present invention relates to a perpendicularly magnetized thin film structure that can ensure perpendicular magnetic anisotropy while transforming a magnetic layer into L10-crystalline structure by oxidizing a metal layer on a magnetic layer by annealing a thin film structure including the magnetic layer and the metal layer, and a method of manufacturing the same.
(b) Description of the Related Art
Since a magnetic body having the L10-crystalline structure has high magnetic anisotropy, it is very useful as a material for information storage. In more detail, a magnetic body having the L10-crystalline structure may be used as a magnetic layer of storing information in a magnetic random access memory (MRAM) or a hard disk drive (HDD). Further, when a magnetic layer having large magnetic anisotropy is used, the magnetization direction of the magnetic layer is not changed by thermal agitation even if the volume of the magnetic layer is small, so that it is possible to highly integrate a memory device.
The material of a typical a magnetic body having the L10-crystalline structure may be FePt, FePd or CoPt. The c axis of the magnetic body having the L10-crystalline structure is an easy-magnetization axis and the magnetic body has perpendicular magnetic anisotropy when the c axis is perpendicularly arranged. In particular, it has been known that the perpendicular anisotropic energy of FePt alloy is large. When a magnetic body having high perpendicular magnetic anisotropy is used as a record layer, information loss due to thermal agitation does not occur even if the volume of the magnetic layer is very small, and a stability factor of the recording layer (KUV/kBT, KU: magnetic anisotropy, V: volume of a magnetic body, kB: Boltzmann constant, T: absolute temperature) becomes very high.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.